This invention involves a composition and a method for the accelerated aging of cheese. In particular, the aging of American cheese, e.g. cheddar cheese, colby cheese, monterey and jack cheese can be accelerated by use of the composition disclosed herein. State of the art technology for accelerated cheese aging typically employs 1 of 2 approaches other than just raising the curing temperature. The first approach utilizes selected microorganisms in addition to the conventional cheesemaking ingredients whereas the second approach advocates the use of enzymes, in some cases from the same class of organisms, which are added during the cheese manufacturing process.
Cheese flavor is a complex mixture of several hundred flavor components. The balance is especially critical to obtaining the typical organoleptic preception associated the cheese flavor. Also, associated with aging is body breakdown or softening. The complexity of the flavor and the opportunity for off-flavor development have precluded the commercialization of an effective cheese aging product.
Associated with the aging and flavor development of cheese is the overall hydrolysis of the major components thereof, i.e. the conversion of protein and fat to peptides and free fatty acids, respectively. Much focus has been placed on the role of lipolytic and proteolytic enzymes, e.g. lipases and esterases, from dairy microorganisms and from rennet during the ripening process. The formation of volatile fatty acids is routinely observed during the ripening process, however, the sources of these lipases and esterases are relatively undefined. Some authors assign lipolytic action to the milk lipase while others believe that contaminating microorganisms such as Micrococci sp. are the source of fat hydrolyzing enzymes. Current theories suggest that the flavor components of cheese are not necessarily the direct result of proteolysis and lipolysis, but instead are the result of precursor compounds generated by the gross hydrolysis of casein and fat which have been further converted by relatively obscure pathways.
The balance of flavor components during cheese aging is a very delicate and complex process. Although the process is not well-understood, certain investigators have developed theories regarding the natural process and have consequently proposed methods to accelerate this process. Kratochvil discloses in U.S. Pat. No. 4,119,732 a process for the manufacture of American cheese which involves the addition of specific pairs of strains of Lactobacillus plantarum and Streptococcus durans in combination with pre-gastric lipases during the cheesemaking process with subsequent curing of the cheese at elevated temperatures. In U.S. Pat. No. 4,158,607, Kalinowski et al disclose an enzymatic preparation composed of the protease from Penicillium candidum or P. roqueforti and the autolysate of a lactic acid bacteria from the species S. lactis or L. casei. International Patent publication No. WO 82/03971 having an international publication date of Nov. 25, 1982, discloses a method of producing a low-fat cheese product which involves inoculating milk with a culture of L. bulgaricus and S. thermophilus together with a culture of L. casei and a normal cheese starter culture. The first two organisms are said to produce the required flavor and rapid fermentation of lactose whereas the L. casei assists in the hydrolysis of protein.
British Pat. No. 1,326,516 describes a process for producing a cheese-like flavoring material. A product prepared using this material would not be considered cheddar cheese as that term is used herein as it is close in concept to enzyme modified cheese. The use of a flavoring organism such as L. lactis or L. casei is described as being optional to this process.
Dooley, in U.S. Pat. No. 4,172,900 describes a composition for addition to cheese milk and/or curd which composition is a blend of a proteolytic enzyme from a viable micrococcus together with pre-gastric lipases and L. lactis, L. bulgaricus or L. casei. This formulation is intended for the enhancement of intensified flavor development rather than accelerated aging.
Roberts, in U.S. Pat. No. 3,650,768 discloses a method of making cheese from heat-treated milk having increased flavor which involves the use of a formulation made up of viable Micrococcus chon and pre-gastric lipase together with viable L. lactis or L. bulgaricus.